The present disclosure relates to electrical device manufacturing, and more particularly to spalling methods.
One method for transferring thin crystalline layers from a source substrate to another substrate (plastic, glass, metal, etc) is controlled substrate spalling. In this method, the surface of a substrate is removed by depositing a stressed material (e.g., metal) on the surface to be cleaved, i.e., base substrate, in which the thickness and stress values of the stressed material are below that required for spontaneous base substrate spalling, but are high enough to permit spalling after fracture initiation. Controlled spalling offers a low cost, simple approach for removing many thin semiconductor layers from a comparatively expensive thick base substrate.